I have converted state highpoint heights to the from NGVD 29 to NAVD 88 data using the USGS Verton calculator.

Interestingly Delaware rather Florida is the big loser in the conversion (the difference in height reflects a 1988 discovery that gravity should have be factored in the 1929 standards for measuring elevations).

Predictably the big mountains all had dramatic increases with Colorado’s Mount Elbert increasing almost 7 feet — it’s conversion was higher than the slightly higher Mount Whitney in California because Whitney is closer to the ocean and thus loses out on the mass calculation.

Read more about the conversion process (and either download the converter or do it online.

The convertor does not calculate Mount McKinley or Mauna Kea because the conversion process is very involved (it is not a clean cut addition to an Excel formula) and the USGS does not have the funding or time to calculate the rest of the U.S. or the world. The look up tables for just the U.S. for the formula are nearly 3 megs!

The table in the second column show current NVGD data rounded to feet, third column shows the heights rounded to feet after the conversion. The fourth column shows the difference in feet after the conversion and the fifth column shows the difference in inches.

State Highpoints Converted to NAVD 88 Heights

State

NGVD 29

NAVD 88

Difference Feet

Difference Inches

Alabama

2407

2407

0.3

3.1

Alaska

20320

20320

0.0

0.0

Arizona

12633

12637

4.4

53.0

Arkansas

2753

2753

0.2

3.0

California

14494

14500

6.1

73.5

Colorado

14433

14440

6.5

78.5

Connecticut

2380

2379

-0.6

-7.8

Delaware

448

447

-1.0

-12.2

Florida

345

345

-0.2

-1.9

Georgia

4784

4784

0.2

2.0

Hawaii

13796

13796

0.0

0.0

Idaho

12662

12668

5.5

66.2

Illinois

1235

1235

-0.2

-2.3

Indiana

1257

1257

-0.4

-5.3

Iowa

1670

1671

0.7

8.4

Kansas

4039

4041

1.6

19.2

Kentucky

4145

4145

-0.3

-3.2

Louisiana

535

535

-0.2

-2.6

Maine

5267

5267

-0.4

-4.9

Maryland

3360

3360

-0.4

-4.9

Massachusetts

3491

3491

-0.5

-5.7

Michigan

1979

1979

0.2

1.9

Minnesota

2301

2302

0.5

6.1

Mississippi

806

806

0.0

0.1

Missouri

1772

1772

0.1

1.1

Montana

12799

12804

5.1

61.8

Nebraska

5424

5427

2.7

32.1

Nevada

13143

13149

6.1

73.3

New Hampshire

6288

6288

0.1

0.7

New Jersey

1803

1802

-0.6

-6.7

New Mexico

13161

13166

5.4

64.3

New York

5344

5344

-0.1

-1.1

North Carolina

6684

6684

0.1

1.0

North Dakota

3506

3508

1.7

21.0

Ohio

1550

1549

-0.6

-7.4

Oklahoma

4973

4975

2.3

27.8

Oregon

11239

11243

4.4

52.4

Pennsylvania

3213

3213

-0.3

-3.6

Rhode Island

812

811

-0.8

-9.4

South Carolina

3560

3560

-0.1

-1.0

South Dakota

7242

7244

2.2

26.5

Tennessee

6643

6643

0.2

2.5

Texas

8749

8751

2.2

26.8

Utah

13528

13534

5.9

71.1

Vermont

4393

4393

-0.1

-1.8

Virginia

5729

5729

0.1

1.0

Washington

14411

14417

6.3

75.7

West Virginia

4863

4863

-0.2

-2.9

Wisconsin

1951

1951

0.1

0.9

Wyoming

13804

13810

5.7

68.5

In posting this one of the helpful links was an online csv to html converter (converting by saving an Excel file to an html table causes problems as Microsoft bloats the conversion). Interestingly this nifty feature has no backwards links at this posting. The site also offers the perl code to run it on your own server.